Tamby, until now head of the bank's banking and securities services in the UK, will be responsible for the group's banking, investment and treasury processing and settlement systems.

Tamby has spent 14 years with the group. He has headed securities services in Madrid and began his career with the bank in the Paris-based capital markets fixed-income trading department.

Warwick Newbury, chief executive of SG Hambros said: "Guy's extensive knowledge of the Société Générale group and his management experience and expertise in operational issues will be invaluable in helping us expand the service of our operational units."